SOURCES TO IMPROVE OXIDATIVE STABILITY IN EDIBLE OILS
By Nia Wiradjaja
11605005
BACHELOR’S DEGREE in
FOOD TECHNOLOGY
LIFE SCIENCES AND TECHNOLOGY
SWISS GERMAN UNIVERSITY The Prominence Tower
Jalan Jalur Sutera Barat No. 15, Alam Sutera Tangerang, Banten 15143 - Indonesia
June 2020
Revision after Thesis Defense on July 10th, 2020
Nia Wiradjaja
STATEMENT BY THE AUTHOR
I hereby declare that this submission is my own work and to the best of my knowledge, it contains no material previously published or written by another person, nor material which to a substantial extent has been accepted for the award of any other degree or diploma at any educational institution, except where due acknowledgement is made in the thesis.
Nia Wiradjaja
_____________________________________________
Student Date
Approved by:
Tabligh Permana, S.Si., M.Si.
_____________________________________________
Thesis Advisor Date
Dr. Hery Sutanto, M.Si.
_____________________________________________
Thesis Co-Advisor Date
Dr. Dipl. -Ing. Samuel P. Kusumocahyo
____________________________________________
Dean Date
Nia Wiradjaja
ABSTRACT
A REVIEW ON THE POTENTIAL OF NATURAL ANTIOXIDANT SOURCES TO IMPROVE OXIDATIVE STABILITY IN EDIBLE OILS
By Nia Wiradjaja
Tabligh Permana, S.Si., M.Si., Advisor Dr. Hery Sutanto, M.Si., Co-Advisor
SWISS GERMAN UNIVERSITY
Edible oils have been used widely to in food processing, especially process with thermal treatment such as frying. In the frying process, oils are usually used repetitively and will trigger the presence of lipid oxidation which will result in the degradation of fatty acids. This degradation of fatty acids will then result in the reduction of quality in oil which include decreasing of nutritional value. The reduction of quality in oil is very dangerous as it can migrate into the food that will be consume by human and trigger several negative health effects such as carcinogenic properties. In order to preserve the quality of the oil, antioxidants are used to improve its oxidative stability. As there are some restrictions and drawbacks of using synthetic antioxidant, natural antioxidants are more preferable to be used in food industry. In this paper, the subject that were reviewed are oils with high polyunsaturated fatty acids content and natural antioxidants that has the potential to improve oxidative stability of the oils which are rosemary extract, sesame seed extract, green tea extract and fruit peels extract. The optimum extraction method and active compounds contained in the extract will also be discussed.
Keywords: Edible Oil, Fatty Acids, Oxidative Stability, Natural Antioxidant, Antioxidant Activity, Optimum Extraction, Active Compound
Nia Wiradjaja
© Copyright 2020 by Nia Wiradjaja All rights reserved
Nia Wiradjaja
DEDICATION
I dedicate this thesis work to my family, advisor and everyone that are interested in this topic.
Nia Wiradjaja
ACKNOWLEDGEMENTS
I would like to express my gratitude to God for his blessing and guidance throughout the process of this thesis work. I would also like to thank the following people who have been giving supports during the completion of this thesis:
1. Tabligh Permana, S.Si., M.Si. and Dr. Hery Sutanto, M.Si. as my thesis advisor and co-advisor for the guidance, supports and motivation on the assembling process of this thesis.
2. Lecturers and staffs of Faculty of Life Science and Technology for the time, supports, experiences and knowledges.
3. Researchers and scientist who provided journals which contributes in my thesis.
4. My parents and beloved sister, Ilona Wiradjaja for the encouragement and financial supports.
5. Alyca Anggita, Steven Nathanael, Richard Dewa Surja, Paskalis Rivaldi, Clarence Sukmana, Claudia Johan, Maria Putri and Kevin Indrayana as my closest friends for giving endless supports and motivations through ups and downs in my life.
6. Fellow friends from Food Technology department and other department for the support, encouragements, knowledge sharing and great memories in SGU.
7. Other people that I cannot mention one by one, that has helped me to complete my thesis.
Nia Wiradjaja
TABLE OF CONTENTS
Page
STATEMENT BY THE AUTHOR ... 2
ABSTRACT ... 3
DEDICATION ... 5
ACKNOWLEDGEMENTS ... 6
CHAPTER 1 – INTRODUCTION ... 12
CHAPTER 2 – METHODOLOGY ... 15
2.1 Venue and Time ... 15
2.2. Methodology ... 15
CHAPTER 3 – LITERATURE REVIEW ... 16
3.1 Fatty Acids in Edible Oils ... 16
3.1.1 Fatty Acids Composition of Several Edible Oil After Deep-Frying ... 19
3.1.1.1 Changes of Polyunsaturated Fatty Acids (PUFAs) After Deep-Frying . 20 3.1.1.2 Changes in Trans-Fat After Deep-Frying ... 21
3.1.1.3 Changes in Monounsaturated Fatty Acid (MUFA) after Deep-Frying .. 23
3.2 Oxidative Stability ... 24
3.3 Improving Oxidative Stability of Several Edible Oils by The Addition of Antioxidant ... 25
3.3.1 Rosemary Extract (Rosmarinus officinalis L.) ... 27
3.3.1.1 The Addition of Rosemary Extract in Edible Oil ... 27
3.3.1.2 Optimum Extraction of Rosemary Extract for Food Application ... 33
Nia Wiradjaja
3.3.2.2. Optimum Extraction Method of Sesame Seed for Food Application .... 38
3.3.3 Green Tea Extract ... 39
3.3.3.1 The Addition of Green Tea Extract in Edible Oil ... 39
3.3.3.2 Optimum Extraction Method of Green Tea for Food Application ... 42
3.3.4 Fruit Peels ... 43
3.3.4.1 Optimum Extraction Method of Apple Peels for Food Application ... 45
3.3.4.2 Optimum Extraction Method of Pomegranate Peels for Food Application ... 46
CHAPTER 4 – CONCLUSIONS AND RECOMMENDATIONS ... 49
4.1 Conclusions ... 49
4.2 Recommendations ... 49
REFERENCES ... 50
CURRICULUM VITAE ... 67
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LIST OF FIGURES
Page
Figure 1. Alpha-linolenic acid (left) and Linoleic acid (right) ... 17
Figure 2. Changes in PUFAs Content in Sunflower Oil, Cottonseed Oil and Soybean Oil ... 20
Figure 3. Changes in Trans-Fat Content in Sunflower Oil, Cottonseed Oil and Soybean Oil ... 22
Figure 4. Changes of MUFA Content in Sunflower Oil, Cottonseed Oil and Soybean Oil ... 23
Figure 5. Rosemary (Rosmarinus officinalis L.) ... 27
Figure 6. Changes of Oxidative Stability Index in Edible Oil with The Addition of Rosemary Extract and TBHQ ... 28
Figure 7. Changes of PUFAs Content in Edible Oil with The Addition of Rosemary Extract and TBHQ ... 29
Figure 8. Changes of Peroxide Value in Soybean Oil with The Addition of Rosemary Extract and BHA+BHT ... 29
Figure 9. Changes of Peroxide Value in Cottonseed Oil with The Addition of Rosemary Extract and BHA+BHT ... 30
Figure 10. Changes of Conjugated Dienes Content in Sunflower Oil with The Addition of Rosemary Extract, BHA, Tocopherol and TBHQ ... 31
Figure 11. Changes of FFA Content in Sunflower Oil with The Addition of Rosemary Extract, BHA, Tocopherol and TBHQ ... 31
Figure 12. Chemical Structure of Carnosic Acid (left) and Carnosol (right) ... 33
Figure 13. Chemical Structure of Rosmarinic Acid ... 33
Figure 14. Sesame Seed (Sesamum indicum) ... 34
Figure 15. Changes of Peroxide Value and TBARS value in Sunflower Oil with The Addition of Sesame Seed Extract and BHT ... 35
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Figure 17. Changes of Conjugated Dienes in Sunflower Oil with The Addition of Sesame Seed Extract, BHA, BHT and TBHQ ... 36 Figure 18. Chemical Structure of Tert-Butylhydroquinone (TBHQ) ... 37 Figure 19. Chemical Structure of Sesamin (left), Sesaminol (middle) and Sesamolin (right) ... 37 Figure 20. Green Tea Leaves ... 39 Figure 21. Changes of Fatty Acids Content in Edible Oil with The Addition of Green Tea Extract ... 39 Figure 22. Butylated Hydroxytoluene (BHT) ... 40 Figure 23. Changes of Peroxide Value in Edible Oil with The Addition of Green Tea Extract and Tocopherol ... 40 Figure 24. Chemical Structure of EC, EGC, ECG and EGCG ... 41 Figure 26. Changes of Conjugated Dienes in Edible Oil with The Addition of Fruit Peels Extract and BHT ... 44 Figure 25. Changes of Peroxide Value in Edible Oil with The Addition of Fruit Peels Extract and BHT ... 44
Nia Wiradjaja
LIST OF TABLES
Page Table 1. Fatty Acids Composition (%) of Several Edible Oils ... 18 Table 2. Potential Temperature of Each Extracts to Improve Oxidative Stability ... 47
